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Photon Antennas 1

They glow in color, coldly
  [vote for,

All this modern wireless communications stuff depends on antennas to broadcast and receive electromagnetic radiation. The simplest antenna is a straight wire. Radio engineers know that the most efficient straight-wire antennas are "full wavelength" -- that is, if the radio waves are 21 centimeters long (a microwave commonly associated with hydrogen molecules), the straight antenna should also be that long.

Well, visible light has a range of wavelengths from 390 nano- meters (violet) to 700 nano-meters (red). Modern semiconductor manufacturing processes are routinely drawing lines that are 1/10 that size and smaller.

So now let us imagine a new type of color display screen. It is a simple flat surface that has been ruled with a vast number of appropriately short antenna-lines. When the right frequency of signal is sent to any one of those antennas, it emits electromagnetic radiation just like your cell phone --except that you will be able to see the waves that get radiated, since they would be of visible-light frequency. Different frequencies and different antennas mean different colors are radiated, of course. And since antenna-radiance is a fairly efficient process, we should be able to get lots of light for minimal energy.

The only drawback, of course, and this is why this Idea is Half- Baked, is that we need our transmitters to generate the appropriate high-frequency signals. Visible-light frequencies range from 430 Terahertz for red light to 770 Terahertz for violet. Still, progress is being made; single-digit Terahertz radiation is getting commonly produced these days. So all we need do is wait for the inevitable future technical advancements, and this Photon Antenna display can become a reality.

Vernon, Sep 30 2015

And it can be powered by light, too... http://phys.org/new...nnaconverts-dc.html
Something poetic about a light powered optical display... [4whom, Oct 01 2015]

Already baked. https://en.m.wikipe...light_communication
Replace antenna with light emitting diode and you are gtg [WcW, Oct 01 2015]

Quantum dot https://en.wikipedia.org/wiki/Quantum_dot
See note about Sony panel [bhumphrys, Oct 03 2015]

Optical dot antenna and nanohole transmission http://www.research...nohole_transmission
cutting edge [bhumphrys, Oct 03 2015]


       My guess would be oscillating electric fields at 100+ THz is going to be very difficult, leading to spontaneous radiation from the wires through which it is conducting.   

       Instead of antennas fed by oscillating electric fields, you could have resonant cavities that are pumped with light. The resonant frequency of the cavities (filled with appropriate material such as quantum dots, photonic crystal etc) could be changed by various ways (piezo electric effect, electro-optic effect) to change the emitted light colour (essentially a tunable laser).
xaviergisz, Oct 01 2015

       [4whom], it would have been more appropriate for that link to have been added to the "Photon Antennas 2" Idea (which I've just done). But thanks, all the same!
Vernon, Oct 01 2015

       [WcW], the point of this Idea is to present something DIFFERENT from what is already available. Besides, I posted an Idea called "Micro-Diode Display Panels" a long time ago! (It is in the Product:Light:LED category.)
Vernon, Oct 02 2015

       Err, err, err, if this is comms by light, then wasps/bees, traffic lights and semaphore have a bit of a head start?
not_morrison_rm, Oct 02 2015

       [Vernon], could it be possible that you have mystically predicted the Sony XBR-55X900A Ultra HD 4K LCD TV? (see link)
bhumphrys, Oct 03 2015

       [bhumphrys], no, an antenna is not generally shaped like a dot.
Vernon, Oct 03 2015

       Well, in general maybe this is so, but somebody needs to let Abhinav Bhardwaj know this; (see link).
bhumphrys, Oct 03 2015


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